1. Field of the Invention
This invention relates to wind turbines and more particularly to wind turbines fabricated from a central flexible beam member supporting aerodynamic blades at the opposite ends thereof and mounted from support structure for rotation about an axis of rotation and free pivot motion about a yaw axis, and with pitch and yaw control capabilities.
2. Description of the Prior Art
It is common practice in wind turbine art to use the wind resistance of the turbine, preferably aided by a weather vane, for yaw control purposes as in U.S. Pat. No. 1,792,212. It has also been conventional practice in wind turbines to either provide no speed control mechanism or to provide complicated speed control mechanism of the type taught in Weeks U.S. Pat. No. 2,215,413 wherein centrifugally responsive weights serve as an overspeed governor to keep the wind turbine at low rotational speed where it unfortunately suffers poor performance.
Further, wind turbines have had yaw control mechanisms which include a wind directional sensor which sends a wind direction signal to a yaw motor which drives the wind turbine in yaw until the signal is reduced to zero. To avoid high gyroscopic loads generated by the wind turbine during its yaw correcting motion, the wind turbine must be motor driven very slowly in yaw. Yaw correction is therefore slow with such a mechanism so that the efficiency of the system is reduced. Contrary to this yaw motion system, our construction does not have to combat gyroscopic loads but utilizes gyroscopic loads beneficially to achieve yaw control.